How to use geometry_msgs/Twist.h ?

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Hello, I'm trying to use stage with ROS. So I have modified the talker.cpp code, from the tutorial, to control the robot of the stage's tutorial. I have changed the declaration of the publisher to this:

 ros::Publisher chatter_pub = n.advertise<geometry_msgs::Twist>("cmd_vel", 1000);

And I add this too:

#include <geometry_msgs/Twist.h>

My problem is that the code cant compile because this library cant be found. The error given by the compiler is :

ros_workspace/stage_controllers/src/talker.cpp:4:33: error fatal: geometry_msgs/Twist.h: No existe el archivo o el directorio compilación terminada.

Its in spanish, but it means: fatal error: geometry_msgs/Twist.h: The file or directory doesn't exist, compilation finished.

I have tried to add the route of this file to the $PATH (/opt/ros/electric/stacks/common_msgs/geometry_msgs/msg_gen/cpp/include/geometry_msgs/Twist.h) and have done all the ros.org tutorial. So where should I add this route to makes it compile? Thanks for your time